feat: PullToRefresh 풀다운 새로고침 컴포넌트

src/components/PullToRefresh.css

@@ -0,0 +1,86 @@
+/* PullToRefresh — pull-down-to-refresh wrapper */
+
+.pull-to-refresh {
+  position: relative;
+  overscroll-behavior-y: contain;
+}
+
+/* Indicator circle */
+.pull-to-refresh__indicator {
+  position: absolute;
+  top: -48px;
+  left: 50%;
+  transform: translateX(-50%);
+  width: 36px;
+  height: 36px;
+  border-radius: 50%;
+  background: var(--surface-card);
+  border: 1px solid var(--border-line);
+  box-shadow: var(--shadow-md);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  opacity: 0;
+  pointer-events: none;
+  transition: opacity 0.18s var(--ease-out);
+  z-index: 10;
+  color: var(--neon-cyan);
+}
+
+.pull-to-refresh__indicator.is-visible {
+  opacity: 1;
+}
+
+/* Spinner */
+.pull-to-refresh__spinner {
+  display: block;
+  width: 20px;
+  height: 20px;
+  border: 2px solid var(--border-line);
+  border-top-color: var(--neon-cyan);
+  border-radius: 50%;
+  animation: ptr-spin 0.7s linear infinite;
+}
+
+@keyframes ptr-spin {
+  to { transform: rotate(360deg); }
+}
+
+/* Arrow chevron */
+.pull-to-refresh__arrow {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 18px;
+  height: 18px;
+  transition: transform 0.2s var(--ease-out);
+}
+
+.pull-to-refresh__arrow.is-ready {
+  transform: rotate(180deg);
+}
+
+/* Content area */
+.pull-to-refresh__content {
+  will-change: transform;
+}
+
+/* Reduced motion */
+@media (prefers-reduced-motion: reduce) {
+  .pull-to-refresh__spinner {
+    animation: none;
+    border-top-color: var(--neon-cyan);
+  }
+
+  .pull-to-refresh__arrow {
+    transition: none;
+  }
+
+  .pull-to-refresh__indicator {
+    transition: none;
+  }
+
+  .pull-to-refresh__content {
+    transition: none !important;
+  }
+}

src/components/PullToRefresh.jsx

@@ -0,0 +1,99 @@
+import { useRef, useState, useCallback } from 'react';
+import { useIsMobile } from '../hooks/useIsMobile';
+import './PullToRefresh.css';
+
+const THRESHOLD = 60;
+const MAX_PULL = 120;
+const RESISTANCE = 0.5;
+const CONTENT_SHIFT_FACTOR = 0.3;
+
+export default function PullToRefresh({ onRefresh, children, className = '' }) {
+  const isMobile = useIsMobile();
+  const [pullY, setPullY] = useState(0);
+  const [state, setState] = useState('idle'); // idle | pulling | ready | refreshing
+  const startYRef = useRef(null);
+  const containerRef = useRef(null);
+
+  const handleTouchStart = useCallback((e) => {
+    const el = containerRef.current;
+    if (!el) return;
+    if (el.scrollTop > 0) return; // only trigger at top
+    startYRef.current = e.touches[0].clientY;
+  }, []);
+
+  const handleTouchMove = useCallback((e) => {
+    if (startYRef.current === null) return;
+    const delta = e.touches[0].clientY - startYRef.current;
+    if (delta <= 0) {
+      setPullY(0);
+      setState('idle');
+      return;
+    }
+    const clamped = Math.min(delta * RESISTANCE, MAX_PULL);
+    setPullY(clamped);
+    setState(clamped >= THRESHOLD ? 'ready' : 'pulling');
+  }, []);
+
+  const handleTouchEnd = useCallback(async () => {
+    if (startYRef.current === null) return;
+    startYRef.current = null;
+    if (state === 'ready') {
+      setState('refreshing');
+      setPullY(THRESHOLD);
+      try {
+        await onRefresh?.();
+      } finally {
+        setState('idle');
+        setPullY(0);
+      }
+    } else {
+      setState('idle');
+      setPullY(0);
+    }
+  }, [state, onRefresh]);
+
+  if (!isMobile) {
+    return <div className={className}>{children}</div>;
+  }
+
+  const indicatorVisible = state !== 'idle';
+  const contentShift = pullY * CONTENT_SHIFT_FACTOR;
+
+  return (
+    <div
+      ref={containerRef}
+      className={`pull-to-refresh ${className}`}
+      onTouchStart={handleTouchStart}
+      onTouchMove={handleTouchMove}
+      onTouchEnd={handleTouchEnd}
+    >
+      <div
+        className={`pull-to-refresh__indicator ${indicatorVisible ? 'is-visible' : ''}`}
+        style={{ transform: `translateY(${pullY}px)` }}
+        aria-hidden="true"
+      >
+        {state === 'refreshing' ? (
+          <span className="pull-to-refresh__spinner" />
+        ) : (
+          <span className={`pull-to-refresh__arrow ${state === 'ready' ? 'is-ready' : ''}`}>
+            <svg width="18" height="18" viewBox="0 0 18 18" fill="none" aria-hidden="true">
+              <path
+                d="M9 3v10M4 8l5 5 5-5"
+                stroke="currentColor"
+                strokeWidth="1.8"
+                strokeLinecap="round"
+                strokeLinejoin="round"
+              />
+            </svg>
+          </span>
+        )}
+      </div>
+      <div
+        className="pull-to-refresh__content"
+        style={{ transform: `translateY(${contentShift}px)`, transition: state === 'idle' ? 'transform 0.3s var(--ease-out)' : 'none' }}
+      >
+        {children}
+      </div>
+    </div>
+  );
+}